New Zealand North to South Island in one month! any advice

Hello

I am in New Zealand for one month only, i fly into the north island and out of the south. Has anyone any recommendations on how to get around quickly? Some people have recommended getting a campervan but not sure how cost affective this is from having hostels and using buses etc?

Any tips would be great thanks!

bus the north island nakedbus.com and citylink.co.nz are great and cheap

you probably have a good idea of what you want to see but I'll point out some musts anyway

-Don't waste anytime in auckland. if you fly in try to book a bus out that same day. should be easy enough. if I ever go back I will book a bus at the airport
-Definitely do the tongariro crossing.
-If you are with some cool people rent a campervan and drive around the coromandel peninsula and camp out where you can. It's really beautiful there. but If you are alone that area might be a little boring.
-hot water beach is pretty neat

south island:
rent a camper van for the south island
-franz josef is a must
-make sure you see lake hawae and lake wanaka in the day light on the way to queenstown. it really is something special. just stunning scenery
-swim with the dolphins or seals in kaikoura. I missed out but my friends all raved about it. they said they were in the water with at least 500 dolphins and that the seals were like big puppies

hey thanks for the tips, thats been great! i do plan to go to lake wanaka as gonna do a sky dive there!
i didnt know u cud swim with dolphins tho, i def want to do that if i can!!